Shrinkage resistance treatment of woolen goods



March 25, 1952 J. ZIMMERMAN ET AL 2,590,811

SHRINKAGE RESISTANCE'TREATMENT 0F wooLEN Goons Filed April 13, 195o 2 SHEETS-SHEET 1 INVENTORS Y ZLNBLNOQ salumi-1o nk/mura John 'Zmmermom I-loxold W. Wolf Louif I. WeLwQf ATTORNEY March 25, 1952 J. ZIMMERMAN ET AL 2,590,811

SHRINKAGE RESISTANCE. TREATMENT oF wooLEN Goons Filed April 15, 195o 2 SHEETS- SHEET 2 A LKALI SoLulLn-vJ 2,

/f VACUUM 'PUMP WW/ Harold W. Wolf I ouf WeLneY BY T/ .6m

ATTORNEY l i L .1 IVENTORS John Zfl'mmefmarw,

Patented Mar. 25, 1952 2,590,811

SHRINKAGE RESISTANCE TREATMENT OF WOOLEN GOODS John Zimmerman, Philadelphia, Pa., Harold W.

' Wolf, Clifton, N. J., and Louis I. Weiner, Philadelphia, Pa.; said Wolf assignor to Forstmann Woolen Company, Passaic, N. J., a corporation of New Jersey n Application April 13, 1950, Serial No. 155,704

17 Claims. (C l. 8-128) This invention relates to a treatment for imparting shrink resistance to woolen garments, and is particularly applicable to knitted woolen body garments such as sweaters and underwear.

2 which may be washed in hot water, without undue shrinkage.

Other objects and advantages of our invention will become apparent from the following detailed Our shrink resistant imparting process is a description of several examples whereby our inchlorination process, wherein the woolen garvention may be practiced. ments are contacted in a closed chamber with In the accompanying drawings: chlorine gas. Basically, a process of this type Fig. 1 is a graph wherein initial moisture conhas been set forth in British Patents Nos. 417,719, tent of a Sweater manufactured in accordance 475,742 and 493,098 and U. S. Patent No. 2,373,974. with Army specifications is plotted against resid- It was heretofore the opinion of the trade that ual chloride content; the moisture content of woolen garments to be Fig. 2 is a graph wherein the residual chloride treated in accordance with dry gaseous chlorinacontent of the same sweater, after dry chlorination methods set forth in the above British tion treatment, is plotted against length shrink,- patents must not exceed 9%, because it was 15 age; thought that a high moisture content of the Fig. 3 is a corresponding graph wherein residwoolen garments would result in irregular and ual chloride content is plotted against wool fiber excessive chlorination and development of depdamage as measured by the alkali solubility test; osition of hydrochloric acid on the goods Fig. 4 is a diagrammatic view of a chamber for (HzO-ClzHOCl-l-HCI), with consequent damthe dry chlorination of woolen garments in acage to the woolen fiber and to the cotton seams cordance with our invention; and holding the parts of the garment together. Fig. 5 is a perspective view of a garment hanger We have found surprisingly, that woolen garprovided with a textile surface or other surface ments may be made shrink resistant by the dry capable of reducing condensation of hydrochloric chlorination method at initial moisture contents acid on a woolen garment hung therefrom during of the goods of from about 10.5% to about 12%, the carrying out of the dry chlorination. without irregularities and hydrochloric acid dam- We have observed in numerous experiments on age, if further precautions, about to be described which the graphs of Figs. 1 to 3 are based, that in detail, are taken to prevent irregular conden- (l) at and above a moisture content of about sation of hydrochloric acid on the goods. On the 10.5% of woolen garments, prior to treatment, other hand, we have found that an initialmoisthe residual chloride content increases in subture content of 9% or less is insufficient to impart stantially linear progression as the initial moisenough shrink resistance through the dry chloture content upon dry chlorination of the garrination method to comply with Armed Forces ments is increased; (2) that the length shrinkage specifications. of a dry chlorinated woolen garment decreases Thus, it is a major object of our invention to sub-stantially inversely proportionally to its residadapt the dry chlorination processes of the aforeual chloride content; and (3) that the damage mentioned patents to the treatment of woolen to the woolen fibers, as measured by thel alkali garments, particularly knit sweaters and undersolubility test, increases substantially proportionwear, for military and civilian uses, wherein a ally to the residual chloride content. On the high degree of shrink resistance is obtained withother hand, we have observed that, as the initial out a substantial sacrifice in strength. moisture content of the chlorinated garments is A further object of our invention is a reducadjusted to less than 10%, the residual chloride tion of the amount of hydrochloric acid deposited content does not drop a linear progression but in on woolen goods treated by the dry chlorination a gradually diminishing curve. The residual method. chloride content imparted by dry chlorination of A further object of our invention is the adjustwoolen garments having an initial moisture conment of the residual chloride content of drytent of less than about 10% is so low that not chlorinated woolen garments to an amount which enough shrinkage resistance is imparted to the imparts the desired shrink resistance to the gargarments to enable them to comply with miliments without substantially impairing their fiber tary specifications or with civilian specifications strength and seam strength. of comparable strictness.

Yet another object of our invention is the pro- As will be seen from Fig. 1 of the drawings, vision of woolen body garments provided with cotthe knee of the curve of the graph which ton seams, as for instance, sleeved sweaters, plots initial moisture content against residual chloride after dry chlorination lies between the moisture content of 9%-10%, corresponding (at 2% chlorination) to a residual chloride content of about 0.9% to about 1.1%. However, the graph of Fig. 2 shows that at a residual chloride content of 1.1%, the length shrinkage of the sweater is still about this is not acceptable in goods for the Armed Forces and in civilian goods that lay claim to being shrink-resistant. Such a sweater would need either dry cleaning or washing in lukewarm water, which in civilian life is often inconvenient and commercially expensive, while under eld conditions in the Armed Forces, such special treatmentv may be wholly unobtainable at times.

Under current military specifications, length or width shrinkage of a sweatershall not exceed 8%. This requirement can be attained by the dry chlorination method if initial moisture content of the goods is adjusted to between about lOl/2% and about 12%, or correspondingly, if the residual chloride content of the dry chlorinated goods is maintained at between about. 1.2% and about 1.7%. At a residual chloride content of about 1.4%, length shrinkage is reduced to. about.

7.5%; the residual chloride content of 1.4%` corresponds to an initial moisture content of the sweater of about 10%%. At aresidual chloride content-of about 1.6% (corresponding to an initial moisture content of about 11i/4%), length shrinkage is almost zero; at this residual chloride content. wool fiber damage, as measured in terms of alkali solubility is about.16.5%, which is within the acceptable limit for Armed Forces woolen garments. Above a residual chloride content of about 1.7% thesweater undergoes an undesired lengthening during hot water washing, while woolv ber damage, as measured by the alkali solubilityl test likewise exceedsv tolerable limits (which are about 18-21%)` as the residual chloride content is substantially increased above 1.7%. Thus, at a residual chloride content below 1.2%- (corresponding to an initial moisture content of below 10%%), chlorination is insufficient to impart acceptable shrinkage resistance to the garment;r and-conversely, above a residual chloridecontent of substantially 1.7% (as the initial moisture-content exceeds about 12%) there is an undesired lengthening of the garment upon washing;v as well as anv unacceptable increase of wool berfdamage. On the other-hand, in the residual chloride content range of from about 1.2% to about 1.7%,there is a give and take in the sense-that shrinkage gradually approaches zero asv the residual chloride content approaches the upperlimit of the foregoing range, while wool fiber damage in terms of the alkali solubilityl test still-remains within acceptable limits within that chloride content range.

We have found that shrink resistance without undue weakening of the wool fabric and cotton seams is achieved by about 11/2% to about 3% chlorination; i. e. by contacting the woolen goods with an atmosphere containing chlorine gas in an amount equal to from about 11/2% to about 3% on the weight of such woolen goods;v With less than 11/2% chlorination, the shrink resistance imparted to the goods is usually insufficient to meet Armed Forces specifications and to come upto a degree of shrink resistance acceptable for better grade civilian goods designated as shrink resistant. OnV the other hand, when chlorination exceeds about 3%, we have observed that damage tothe wool and to the cotton seams isfrequently incurred. We prefer to use 2% chlodll rination and to admit the chlorine gas at the rate of about 4 pounds per hour into an autoclave having an average load, e. g. sweaters weighing 1 lb. 1 oz. each or a total of about 80 pounds. The goods should preferably remain in contact with the chlorine gas for about 30 to 40 minutes. For best results the temperature in the autoclave should be maintained at a temperature above about 70 F., preferably near about 80 F., as below 70 F. undesired condensation of HCl takes place.

If chlorination is at other than the 2% rate, residual chloride content of the treated goods changes: correspondingly. Thus; it was determined that whilev a sweater with 11% moisture content prior to chlorination received a 1.3% residual chloride content as the result of 2% chlorination (i. e. exposure to chlorine gas weighing 2% of the sweaters weight) the same initial moisture content (11%) resulted in a residual chloride content of 1.4% after 3% chlorination.

The chlorination chamber may be evacuated prior. to admission of the chlorine gas (e. g. as4 described in British Pat. #417,719); but this is not necessary for the successful operation of our process, which can be. ipracticedby introducing chlorine gas into the chamber. containing sweaters at atmospheric pressure.` We prefer to recirculate the chlorine gas, for reasons of economy,`

and for more even and thorough chlorination of the goods. The chlorination chamber should be pressure-tight, for obvious reasons.

Adjustment of the pH of the woolenY goods (e. g. sweaters) prior to chlorination to the acid side, by pretreatment with acids down to a. pH of about 3 (such as acetic, imparting a pH of about 4.5, or formic acid, imparting a pH of about 3.3), was found to have littlel if any, effectY on the breaking strength and seam failures of the goods after chlorination. Upward pH adjustment up to about 9, e. g. by a corresponding pretreatment with a mildalkali such as sodium bicarbonate likewise. had no substantial effect in terms of breaking strength and searnV failures, but above a pH of about 8 appeared to lessen the shrink resistance impartedby the. dry chlorination process. The methodof determining pH of a water extractof the woolen goods isA accomplished in accordance with. the procedure described in Federal Specification CCC-T-19la, section VII, par. 1a (3)1,.Supplement, October. 8, 1945, page 48.

We have found that damage to woolengarments, caused by uneven deposition thereon. ofl hydrochloric acid during the dry chlorination step can be avoided Iby suspending each garment individually from a. hanger Il having a noncondensing, hygroscopic surface. I2, and with a.

low heat capacity. We prefer wool-covered hangers. but have found other textile-covered hangers, e. g. hangers covered with nylonbers, glass fibers or mixtures of theseberswith wool fibers, to be usefulfor this purpose. While the base material ofthe hangers may be any. suitable substance (wood, plastic), we prefer aconventional wire hanger for reasons of cheapness and overall sturdiness.'

After the garmentsv are placed on covered hangers as described, they should be introduced into the pressure-resistant autoclave I3 by suspending the hangers within such autoclave, e. g. from horizontal rods I4. It is undesirable to pack the garments too tightly together, because it is essential for uniform chlorination that the chlorine gas be permitted to circulate into contact with all parts of the goods; for this reason, the garments should be spaced from each other and from the walls of the chamber.

Even with the foregoing precaution, it is necessary to submit the goods to a neutralization treatment after completion of the chlorination step, to remove excess residual acid which, if permitted to remain on the goods, would weaken the wool fabric and particularly the cotton seams. Five per cent sodium bicarbonate (based on the weight of the load) is suitable. The treatment is conveniently accomplished in a loose stock dye machine having an approximate :1 or 20:1 liquor ratio. The treatment may be carried out at room temperature for a period of about 15 to 20 minutes followed by a brief rinse. The efcacy of the last rinse can be increased by adding conventional cationic finishing agents. Other weak alkalies, e. g. sodium carbonate or ammonium hydroxide may be used instead of sodium bicarbonate.

The following examples illustrate severaltypical treatments of woolen sweaters in accordance with our invention:

Example I 75 woolen sweaters (S0 lbs), finished .with cotton seams, and with a controlled moisture content of 10.5%, were placed on individual woolcovered wire hangers and loosely placed in an autoclave. The autoclave was exhausted to a vacuum of about 26" of Hg, and 1.6 pounds of chlorine gas were admitted at a rate of 4 pounds per hour. Contactbetween chlorine and sweaters was maintained for about minutes. The

sweaters were then removed from the autoclave Eccample II The treatment described in Example I was repeated with sweaters whose moisture content had been adjusted to 11%. The median residual chloride content of five sweaters picked at random from the treated lot was 1.5%; alkali solubility 15.0%; length shrinkage 4.3%.

Example III The procedure of Example I was repeated with a lot of sweaters whose moisture content had been adjusted to 11%%. The median residual chloride content of three sweaters picked at random from the treated lot was 1.6% valkali solubility 16.2%; length shrinkage 1.4%..

In a control experiment, wherein initial moisture content in the sweater was adjusted to 8%, residual chloride content was only .7% after dry chlorination, and length shrinkage was about 25%.

The residual chloride content of the woolen goods is a measure of the degree of chlorination, and may be determined by the following test: Take 1.5 grams chlorinated wool, place in stoppered bottle containing 75 ml. liquor made up of 73 ml. distilled water and 2 ml. normal sodium carbonate. Sample should be pulled apart and allowed to stand over night or be shaken for 1/2 to 1 hour. Filter off and take ml. of filtrate for analysis. Acidify with 2 or 3 drops concentrated nitric acid and add exactly 10 ml. decinormal silver nitrate. Then add 5 ml. nitrobenzene to coagulate the precipitate. Add l/2 to 21/2 ml. ferrie alum indicator and titrate with decinormal potassium thiocyanate.

Example Chloride content per milliliter=%=0. 00355 gram Residual chloride 3. l X0. 040355 50 X 1 36 Residual chloride =1. 2l per cent The alkali solubility test, as -a measure of wool ber damage, is described in Federal Specication CCC-T-l91, sec. VII, par 3a (3) Supplement, October 8, 1945, page 49. It essentially consists of placing a sample of wool in 100 ml. of N/10 sodium hydroxide for 1 hour at 65 C., followed by rinsing and drying; The alkali solubility is the resulting per cent loss suffered by the sample.

wherein Wn is Weight prior to treatment and Wt is weight after treatment. The quality loss expressed by this test expresses the fiber damage caused by the shrink resistance imparting treatment, chiefly believed to be due to a partial splitting of the disulfide cross link-ages of the wool structures.

A standard test for shrink resistance is carried out as follows: The woolen garments are washed in water at 140 F., not over 50 p. p. rn. hardness and buffered to a pH of 7. A six pound load is introduced in a standard rotary reversing type washing machine having a cylinder which measures 24 inches in diameter by 24 inches in length and agitated therein with such water for 1 hour. Thereafter, the garments are centrifuga-Hy extr-acted, and dried in a 36 x 24 inch tumbler drier at F. for 30 minutes. The shrinkage loss is computed by dividing the difference in length l00=alkali solubilty (per cent) g before and after washing by the length before Washing and multiplying this fraction by 100.

Iig-L WX l00=1ength shrinkage (per cent) wherein Lo is length prior to washing and Lw is length after washing.

Repeated tests on a considerable number of woolen sweaters, finished with cotton seams, showed conclusively that maximum resistance to shrinkage with minimum chemical damage to the Wool 4and particularly to the cotton seams is obtainable by the dry chlorination process only if the residual chloride content of the treated goods is controlled by adjusting the moisture content of the goods prior to introduction into the chlorination chamber within the ranges disclosed in this specification. If this precaution is taken, and if the goods are subsequently neutralized as herein described, the surprising result is obtained that garments are not only not weakened, but their seam vbreaking strength is actually in creased. Thus, in one 1ot of sweaters, the seam breaking strength of the untreated sweaters was measured to be 38 pounds, while the seam breaking strength of the treated sweater rose to 46 pounds. In another sweater lot, seam breakage strength of an untreated sweater was 51 pounds, and 53 pounds in the treated sweater.

Sweaters and wool garments treated in accordance with the present invention were found in eld tests to remain serviceable after eld army mobile launderings, while untreated sweaters shrank beyond serviceability after the third laundering. The appearance and comfort of the garments are equal or superior to untreated ones.

Dry chlorination in accordance with the present invention is not only applicable to wool sweaters, but to other woolen garments as, for instance, anklets, murders, underwear, jerseys, and shirts. Part wool mixed fabric garments (e. g. part cotton, part wool) are likewise rendered shrink resistant by dry chlorination in accordance with our invention.

While the foregoing examples illustrate specific applications of the principle of our invention, they are not to be taken as a limitation of the scope of our invention to the particular methods set forth therein. Modifications and additional examples will be readily apparent to the expert as" the result of our disclosure. We thus intend to claim our invention broadly and to be limite-d only by the appended claims.

We claim:

1. The process of imparting shrink-resistance to woolen goods without substantially impairing their strength. comprising adjusting the moisture content of said lgoods to from about 10.5% to about 12 contacting said goods in a closed chamber at a temperature above 7 0 F. with from about 11/2 to 3% chlorine gas based on the weight of said goods, and neutralizing the hydrochloric acid formed on said goods.

2. The process of imparting shrink-resistance to woolen goods without substantially impairing their strength, comprising adjusting the moisture content of said goods to from about 10.5% to about 12%, contacting said goods in a closed chamber at reduced pressure with from about 11/2 to 3% chlorine gas based on the weight of said goods, and neutralizing the hydrochloric acid formed on said goods.

3. The process of imparting shrink-resistance to woolen goods without substantially impairing their strength, comprising adjusting the moisture content of said goods to from about 10.5% to about 12%, contacting said goods in the moistened state in a closed chamber at a temperature above 70 F. with from about 11/2 to 3% chlorine gas based on the weight of said goods until the residual chloride content of said goods is from about 1.2% to about 1.7%, and neutralizing the hydrochloric acid formed on said goods.

4. The process of imparting shrink-resistancev to woolen goods without substantially impairing their strength, comprising adjusting the moisture content of said goods to from about 10.5% to about 12%, contacting said garments in a closed chamber with from about 11/2 to 3% chlorine gas based on the weight of said goods until the residual chloride content of said goods is from about 1.2% to about 1.7 and neutralizing the hydrochloric acid formed on said goods.

5. The process of imparting shrink-resistance to woolen goods without substantially impairing their strength, comprising adjusting the surface pH value of said goods to between about 3 and about 8, adjusting the moisture content of said goods to from about 10.5 to about 12%, contactsaid garments in a closed chamber at reduced pressure above 70 F. with from about 11/2 to 3% chlorine gas based on the weight of said goods until the residual chloride content of said goods isfrom about 1.2% to about 1.7%, and neutralizing the hydrochloric acid formed on said goods.

6. The process of imparting shrink-resistance to woolen goods without substantially impairing their strength, comprising adjusting the moisture content of said goods to about 11%, contacting said goods in a closed chamber with from about 11/2 to 3% chlorine gas based on the weight of said goods, and neutralizing the hydrochloric acid formed on said goods.

7. The process of imparting shrink-resistance to woolen goods without substantially impairing their strength, comprising adjusting the moisture content of said goods to about 11%, contacting said goods in the moistened state in a closed chamber with from about 11/2 to 3% chlorine gas based on the weight of said goods until the residual chloride content of said goods is about 1.6%, and neutralizing the hydrochloric acid formed on said goods.

8. The process of imparting shrink-resistance to woolen goods without substantially impairing their strength, comprising adjusting the moisture content of said goods to from about 10.5% to about 12%, contacting said goods in a closed chamber with from about 11/2 to 3% chlorine gas based on the weight of said goods and neutralizing the hydrochloric acid formed on said goods.

9. The process of imparting shrink-resistance to woolen goods Without substantially impairing their strength, comprising adjusting the moisture content of said goods to from -about 10.5% to about 12%, contacting said goods in a closed chamber with about 2% chlorine gas based on the weight of said goods, and neutralizing the hydrochloric acid formed on said goods.

10. The process of imparting shrink-resistance to a woolen body garment without substantially impairing its strength, comprising adjusting the moisture content of said garment to from about 10.5% to about 12%, placing said moistened garment on a textile-covered hanger, contacting said garment in the moist state while on said hanger in a elo-sed chamber with from about 11/2 to 3% chlorine gas based on the weight of the wool until the residual chloride content of said garment is from about 1.2% to about 1.7%, and neutralizing the hydrochloric acid formed on said garment.

11. The process of imparting shrink-resistance to a woolen body garment without substantially impairing its strength, comprising adjusting the moisturecontent of said garment to from about 10.5% to about 12%, placing said moistened garment on a textile-covered hanger, contacting said garment in the moist state while on said hanger in a closed chamber at a temperature above 70 F. with from about 11/2 to 3% chlorine gas based on the weight of the wool, and neutralizing the hydrochloric acid formed on said garment; whereby condensation of acid at the line of contact between said garment and said hanger and local damage to the garment in the area adjacent said line of contact are avoided.

12. The process of imparting shrink-resistance to a woolen body garment Without substantially impairing its strength, comprising adjusting the moisture content of said garment to from about 10.5% to about 12%, placing said moistened garment on a textile-covered hanger, contacting said garment while on said hanger with from about 11/2 to 3 chlorine gas based on the Weight of the Wool in a closed chamber, and neutralizing acid formed on said garment.

13. The process of imparting shrink-resistance to a woolen body garment without substantially impairing its strength, comprising adjusting the moisture content of said garment to from about 10.5% to about 12%, placing said moistened garment on a wool-covered hanger, contacting said garment in the moist state while on said hanger in a closed chamber, with from about 11/2 to 3% chlorine gas based on the weight of the wool in said garment, and neutralizing acid formed on said garment; whereby condensation of acid at the line of contact between said garment and said hanger and local damage to the garment in the area adjacent said line of contact are avoided.

14. The process of imparting shrink-resistance to a woolen body garment without substantially impairing its strength, comprising adjusting the moisture content of said garment to from about 10.5% to about 12%. placing said moistened Vgarment on a nylon-covered hanger, contacting said garment in the moist state while on said hanger in a closed chamber, with from about 11/2 to 3% chlorine gas based on the weight of the wool, and neutralizing acid formed on said garment; whereby condensation of acid at the line of contact between said garment andsaid hanger and local damage to the garment in the area adjacent said line of contact are avoided.

15. The process of imparting shrink-resistance to -a woolen body garment without substantially impairing its strength, comprising adjusting the moisture content of said garment to from about 10.5% to about 12%, Placing said mostened garment on a glass-fiber-covered hanger, contacting said garment in the moist state while on said hanger in a closed chamber, with from about 11/2 to 3% chlorine gas based on the weight of the Wool, and neutralizing acid formed on said garment; whereby condensation of acid at the line of contact between said garment and said hanger and local damage to the garment in the area adjacent said line of contact are avoided.

16. The process of imparting shrink-resistance to a woolen body garment without substantially impairing its strength, comprising adjusting the moisture content of said garment to from about 10.5% to about 12%, placing said moistened garment on a hanger having a hygroscopic non-condensing low heat capacity surface, contacting said garment in the moist state while on said hanger in a closed chamber, with from 11/2 to 3 chlorine gas based on the weight of the wool, and neutralizing acid formed on said garment; whereby condensation of acid at the line of contact between said sarment and said hanger and local 10 damage to the garment in the area adjacent said line of contact are avoided.

17. The process of imparting shrink-resistance to woolen garments without substantially impairing their strength, comprising adjusting the moisture content of said garments to from about 10.5% to about 12%, placing each of a plurality of said woolen garments on an individu-al textilecovered hanger, introducing said garments in the moistened state and while on hangers into a closed chamber in spaced relation from each other, circulating from about 11/2 to 3% chlorine gas based on the weight of the wool through said chamber and freely around said garments, removing said garments from said chamber, and neutralizing acid formed on said garments; whereby said woolen garments are uniformly chlorinated and whereby condensation of acid at the line of contact between said garments and said hangers `and local damage to the garments in the area adjacent said line of contact are avoided.

JOHN ZIMMERMAN. HAROLD W. WOLF. LOUIS I. WEIlNER.

REFERENCES CITED The following references are of record in the OTHER REFERENCES Dolby: New Chlorination Process for the Pro duction of Unshrinkable Wool. Textile Colorist, May 1944, pages 212, 213. 8-128.

Zeidler: Woolz Shrinkproofing. 'Through J. Text. Inst., February 1943, page A 86. 8-128.

Whewell et al: Action of Halogens onWool." Through J. Soc. Dyers and Colourists, August 1944, page 220. Abstracts. 

1. THE PROCESS OF IMPARTING SHRINK-RESISTANCE TO WOOLEN GOODS WITHOUT SUBSTANTIALLY IMPAIRING THEIR STRENGTH, COMPRISING ADJUSTING THE MOISTURE CONTENT OF SAID GOODS TO FROM ABOUT 10.5% TO ABOUT 12%, CONTACTING SAID GOODS IN A CLOSED CHAMBER AT A TEMPERATURE ABOVE 70* F. WITH FROM ABOUT 1 1/2 TO 3% CHLORINE GAS BASED ON THE WEIGHT OF SAID GOODS, AND NEUTRALIZING THE HYDROCHLORIC ACID FORMED ON SAID GOODS. 